Double printing unit of a rotary printing machine

Abstract

Large throw-off distances of the transfer cylinders in a double printing unit of a rotary printing machine operating on the rubber/rubber principle are achieved by enabling the two transfer cylinders to be set away from each other, and enabling the two form cylinders to be set away from the respective transfer cylinder. The form cylinder and the transfer cylinder of each printing unit have a drive connection via spur gears, the transfer cylinders are not in tooth engagement via their spur gears, and each printing unit has its own electric motor.

We claim:  
     
       1. A double printing unit of a rotary printing machine comprising: 
       two printing units each having a form cylinder, a corresponding transfer cylinder and an electric motor as a drive, said transfer cylinders being thrown onto each other to print both sides of a web passing between them in a rubber/rubber principle and being set away from each other in order to switch off the double printing unit, said form cylinders being adapted to be selectively set away from its respective transfer cylinder; and  
       a drive connection between each form cylinder and corresponding transfer cylinder of each of said two printing units, said drive connection comprising spur gears operatively connected to said form and transfer cylinders, wherein said transfer cylinders of each of the two printing units are not connected via a toothed engagement of said spur gears.  
     
     
       2. The double printing unit in accordance with claim  1 , further comprising eccentric bushes for mounting said form cylinders and said transfer cylinders. 
     
     
       3. The double printing unit in accordance with claim  1 , further comprising: 
       a frame; and  
       a plurality of supports pivotally mounted in said frame, said plurality of supports mounting said form and transfer cylinders in the double printing unit.  
     
     
       4. The double printing unit in accordance with claim  1 , wherein said form cylinders are adapted to be fitted with printing form sleeves. 
     
     
       5. The double printing unit in accordance with claim  1 , wherein said form cylinders are adapted to be fitted with printing plates. 
     
     
       6. The double printing unit in accordance with claim  1 , wherein said transfer cylinders are adapted to be fitted with rubber blankets. 
     
     
       7. The double printing unit in accordance with claim  1 , wherein said transfer cylinders are adapted to be fitted with rubber sleeves. 
     
     
       8. The double printing unit in accordance with claim  3 , wherein said frame comprises side walls and wherein said form cylinders and said transfer cylinders are mounted on both sides in said side walls. 
     
     
       9. The double printing unit in accordance with claim  8 , wherein one of said side walls comprises an opening on an operating side, said opening being adapted to enable one of a printing form and transfer form to be slid off an adjacent corresponding cylinder. 
     
     
       10. The double printing unit in accordance with claim  3 , wherein said frame comprises side walls and wherein said form and transfer cylinders are cantilevered mounted in one of said side walls.